1,720,966 research outputs found
A Multi-matrix E-nose with Optimal Multi-ranged AFE Circuit for Human Volatilome Fingerprinting
Full text linkSince hundreds of volatile organic compounds (VOCs) produced by cell metabolism and released into the blood are excreted through exhaled breath or body fluids, the volatile composition (volatilome) of human samples reflects a subject’s state of health and early signals any abnormal deviation from healthy to disease. The chemical volatilomic profile of biological matrices can be transduced in a digital fingerprint by low cost and easy-to-use electronic nose (e-nose) devices based on gas sensor arrays. The e-noses can be used to aid clinical diagnosis supporting conventional diagnostic methods that sometimes require expensive or invasive medical procedures and delays in diagnoses. In this paper, an e-nose devoted to the human volatilome fingerprinting is presented. The device, code-named SPYROX, adopts an array of 8 metal-oxide (MOX) gas sensors and it is able to analyze response signals from different matrices (multi-matrix samples), dealing with exhaled breath and headspace analysis of human biological samples. While other works in literature neglect the design of the interface circuit, here an optimal multi-ranged analog front-end (AFE) circuit is proposed. It aims to the optimization of the read-out sensitivity which, ultimately, leads to accurate training datasets and, consequently, to high classification scores. Finally, the efficacy of the device is proved by testing both chemical standards and mixtures. As a result, a classification accuracy of 100% is achieved with a linear discriminant model. The experimental results give a proof on the system’s efficacy to the fingerprint analysis of complex gas mixtures, which are typical of human volatilome
Neural-network-driven Electronic Nose Enhancing Artificial Olfaction in Non-invasive Diagnostics
No full textThis paper presents an e-nose specifically designed for non-invasive diagnostics and human volatilome analysis. The sensing technology is based on a 10-sensors array of both commercial Metal Oxide (MOX) gas sensors and custom-fabricated counterparts. Thanks to a versatile pneumatic system, it is capable of analyzing response signals from various sample types, including exhaled breath and the headspace of human biological samples. A neural-network-based model is adopted to enhance the classification capability. The device's effectiveness is demonstrated through experimental tests with both chemical standards and mixtures resembling human biosamples, achieving a 97.1% classification accuracy with 7 prepared test samples. The experimental results, along with the capability to discriminate correctly the test samples in presence of water, confirm the system's efficacy in the context of non-invasive diagnostics and human volatilome analysis
A novel human biomonitoring study by semiconductor gas sensors in exposomics: Investigation of health risk in contaminated sites
Full text linkTwo areas in central-southern Italy Land of Fires in Campania and Valley of Sacco river in Lazio are known to be
contaminated sites, the first due to illegal fly-tipping and toxic fires, and the second due to an intensive industrial
exploitation done by no-scruple companies and crooked public administration offices with dramatic conse
quences for environment and resident people. The work is intended to contribute to Human BioMonitoring
(HBM) studies conducted in these areas on healthy young male population by a semiconductor gas sensor array
trained by SPME-GC/MS. Human semen, blood and urine were investigated. The fingerprinting of the Volatile
Organic Compounds (VOCs) by a gas sensors system allowed to discriminate the different contamination of the
two areas and was able to predict the chemical concentration of several VOCs identified by GC/MS
Electronic Olfaction and Advanced Gas Sensing for Exposomics: Classification of Human Biosamples from Different Geographic Areas
No full textThis study investigates the potential of electronic olfaction technology and advanced gas sensors as novel tools for digital fingerprinting of the human volatilome in biomonitoring applications. The SPYROX e-nose, enhanced with a hardware add-on to enrich sensors’ responses, is adopted for the direct assessment of biological exposure. Guided by the exposome concept, the experimental approach aims to the classification of urine samples from healthy young subjects residing in two areas of Southern Italy with contrasting environmental conditions (high vs. low pollution). The promising classification accuracy of 83% demonstrates that a low-cost, portable, and easy-to-use device serves as an effective solution for analyzing complex biological samples. This highlights the potential of the SPYROX e-nose to complement traditional biomonitoring methods, identify at-risk populations, and support public health interventions by linking environmental conditions to molecular health indicators
Molecular Alterations and Severe Abnormalities in Spermatozoa of Young Men Living in the “Valley of Sacco River” (Latium, Italy): A Preliminary Study
Full text linkThe Valley of Sacco River (VSR) (Latium, Italy) is an area with large-scale industrial chemical production that has led over time to significant contamination of soil and groundwater with various industrial pollutants, such as organic pesticides, dioxins, organic solvents, heavy metals, and particularly, volatile organic compounds (VOCs). In the present study, we investigated the potential impact of VOCs on the spermatozoa of healthy young males living in the VSR, given the prevalent presence of several VOCs in the semen of these individuals. To accomplish this, spermiograms were conducted followed by molecular analyses to assess the content of sperm nuclear basic proteins (SNBPs) in addition to the protamine-histone ratio and DNA binding of these proteins. We found drastic alterations in the spermatozoa of these young males living in the VSR. Alterations were seen in sperm morphology, sperm motility, sperm count, and protamine/histone ratios, and included significant reductions in SNBP–DNA binding capacity. Our results provide preliminary indications of a possible correlation between the observed alterations and the presence of specific VOCs
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Seminal VOCs Analysis Investigating Sperm Quality Decline—New Studies to Improve Male Fertility Contrasting Population Ageing
No full textThe world is impacting with a drastic demographic change that is reflected in a progressive ageing population. If on the one side increasing health care for older people is important, stimulating the level of birth becomes decisive. The principal goal of this work is to set up of new method for early diagnosis of male infertility based on analysis of seminal Volatile Organic Compounds (VOCs), potentially biomarkers of infertility status. The identification of the volatile metabolite patterns in semen samples was done by an unconventional GC/[−MS + gas sensor] system. Once validate this approach could integrate and improve traditional semen analysis based on physiological parameters and addressed to the development of novel medical devices based on gas microsensors for male infertility screening
Characterization of Human Semen by GC-MS and VOC Sensor: An Unexplored Approach to the Study on Infertility
No full textInfertility is one of principal health and social problems of this century. Male factors are involved in half of the cases and often the alteration concerns sperm motility. Seminogram is the gold standard technique for semen analysis, but it presents several limits. For this reason, we propose a new method for discriminating
asthenozoospermic samples (low sperm motility) from normozoospermic ones (progressive motility > 32%) based on the never explored analysis of the volatile
metabolites in the headspace of human semen sample by Gas Chromatograph (GC) equipped with two detectors: aMass Spectrometer (MS) and a metal oxide based gas sensor sensitive (MOX) to Volatile Organic Compounds (VOCs). VOC sensor signal profiles (resistance vs. time) showed a higher sensitivity to specific organic classes such as aldehydes and ketones. The sensorgrams were preprocessed and analysed by PLS-DA. The results showed that sensorgrams analysis by suitable bioinformatics techniques has a good discrimination power and could support physiological parameters in human semen assessment. The analysis of the human semen Volatilome may be a proof-of-concept for the development of a novel micro-GC device with a sensor array detector, a potential candidate for infertility assessment in clinical practice
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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